Using signal power levels for coexistence among multiple wireless communication technologies

ABSTRACT

Apparatus having corresponding methods and computer-readable media comprise: a transmitter configured to transmit, according to a first protocol, first wireless signals in a first frequency band; and a receiver configured to receive, according to a second protocol, second wireless signals in a second frequency band, wherein the second frequency band is adjacent to or overlaps the first frequency band; and an arbiter configured to allow the transmitter to transmit the first wireless signals according to the first protocol while the receiver receives the second wireless signals according to the second protocol responsive to at least one of i) a signal power level of the first wireless signals being less than a first signal power threshold; and ii) a signal power level of the second wireless signals being greater than a second signal power threshold.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Non-Provisional patentapplication Ser. No. 13/553,146, filed on Jul. 19, 2012 (now U.S. Pat.No. 9,014,751) which claims the benefit of U.S. Provisional PatentApplication Ser. No. 61/522,149, filed on Aug. 10, 2011, entitled “Useof Signal Power Levels for In-device Co-existence Scheduling,” thedisclosures thereof incorporated by reference herein in their entirety.

FIELD

The present disclosure relates generally to the field of wirelesscommunication. More particularly, the present disclosure relates toavoiding interference between different wireless communicationtechnologies that use adjacent or overlapping frequency bands.

BACKGROUND

The popularity of multiple wireless communication technologies forhandheld platforms has created a need to integrate wirelesscommunication technologies on a single wireless communication device.However, the frequency bands of some of these technologies are closeenough to result in interference. For example, the un-licensed 2.4 GHzIndustrial, Scientific and Medical (ISM) frequency band is adjacent tosome of the bands used by Mobile Wireless Standards (MWS) technologiesto result in adjacent channel interference. In many electronic devicessuch as smartphones, both ISM and MWS technologies are implemented inthe same device. For example, a smartphone may employ LTE (Long TermEvolution) for phone calls, WiFi for local area networking, andBluetooth for headsets. LTE transmissions from the smartphone will causeadjacent channel interference with incoming Bluetooth and WiFi signals.Similarly, Bluetooth and WiFi transmissions from the smartphone willcause adjacent channel interference with incoming LTE signals. Thisadjacent channel interference can significantly degrade performance notonly at the smartphone, but also at connected MWS base stations.

SUMMARY

In general, in one aspect, an embodiment features an apparatuscomprising: a transmitter configured to transmit, according to a firstprotocol, first wireless signals in a first frequency band; and areceiver configured to receive, according to a second protocol, secondwireless signals in a second frequency band, wherein the secondfrequency band is adjacent to or overlaps the first frequency band; andan arbiter configured to allow the transmitter to transmit the firstwireless signals according to the first protocol while the receiverreceives the second wireless signals according to the second protocolresponsive to at least one of i) a signal power level of the firstwireless signals being less than a first signal power threshold; and ii)a signal power level of the second wireless signals being greater than asecond signal power threshold.

Embodiments of the apparatus can include one or more of the followingfeatures. In some embodiments, the first protocol is a Mobile WirelessStandards (MWS) protocol; and the second protocol is an Industrial,Scientific and Medical (ISM) band protocol. In some embodiments, thefirst protocol is an Industrial, Scientific and Medical (ISM) bandprotocol; and the second protocol is a Mobile Wireless Standards (MWS)protocol. In some embodiments, each of the first protocol and the secondprotocol, is an Industrial, Scientific and Medical (ISM) band protocol.In some embodiments, the arbiter is further configured to change areceive mode for the receiver responsive to at least one of i) thesignal power level of the first wireless signals not being less than thefirst signal power threshold, and ii) the signal power level of thesecond wireless signals not being greater than the second signal powerthreshold. In some embodiments, the arbiter is further configured tochange at least one of a transmit mode and a signal power level for thetransmitter based on at least one of i) the signal power level of thefirst wireless signals not being less than the first signal powerthreshold, and i) the signal power level of the second wireless signalsnot being greater than the second signal power threshold. In someembodiments, the arbiter is further configured not to allow thetransmitter to transmit the first wireless signals according to thefirst protocol while the receiver receives the second wireless signalsaccording to the second protocol responsive to i) a priority of thefirst wireless signals being less than a priority of the second wirelesssignals, and ii) at least one of a) the signal power level of the firstwireless signals not being less than the first signal power threshold,and b) the signal power level of the second wireless signals not beinggreater than the second signal power threshold. Some embodimentscomprise an electronic device comprising the apparatus of.

In general, in one aspect, an embodiment features a method comprising:transmitting, according to a first protocol, first wireless signals in afirst frequency band while receiving, according to a second protocol,second wireless signals in a second frequency band that is adjacent toor overlaps the first frequency band, responsive to at least one of i) asignal power level of the first wireless signals being less than a firstsignal power threshold, and ii) a signal power level of the secondwireless signals being greater than a second signal power threshold.

Embodiments of the method can include one or more of the followingfeatures. In some embodiments, the first protocol is a Mobile WirelessStandards (MWS) protocol; and the second protocol is an Industrial,Scientific and Medical (ISM) band protocol. In some embodiments, thefirst protocol is an Industrial, Scientific and Medical (ISM) bandprotocol; and the second protocol is a Mobile Wireless Standards (MWS)protocol. Some embodiments comprise changing a receive mode forreceiving the second wireless signals responsive to at least one of i)the signal power level of the first wireless signals not being less thanthe first signal power threshold, and ii) the signal power level of thesecond wireless signals not being greater than the second signal powerthreshold. Some embodiments comprise changing at least one of a transmitmode and a signal power level for transmitting the first wirelesssignals responsive to at least one of i) the signal power level of thefirst wireless signals not being less than the first signal powerthreshold, and ii) the signal power level of the second wireless signalsnot being greater than the second signal power threshold. Someembodiments comprise not transmitting the first wireless signals whilereceiving the second wireless signals responsive to a priority of thefirst wireless signals being less than a priority of the second wirelesssignals and at least one of i) the signal power level of the firstwireless signals not being less than the first signal power threshold;and ii) the signal power level of the second wireless signals not beinggreater than the second signal power threshold.

In general, in one aspect, an embodiment features computer-readablemedia embodying instructions executable by a computer in an electronicdevice to perform functions comprising: causing the electronic device totransmit, according to a first protocol, first wireless signals in afirst frequency band while the electronic device receives, according toa second protocol, second wireless signals in a second frequency bandthat is adjacent to or overlaps the first frequency band, responsive toat least one of i) a signal power level of the first wireless signalsbeing less than a first signal power threshold; and ii) a signal powerlevel of the second wireless signals being greater than a second signalpower threshold.

Embodiments of the computer-readable media can include one or more ofthe following features. In some embodiments, the first protocol is aMobile Wireless Standards (MWS) protocol; and the second protocol is anIndustrial, Scientific and Medical (ISM) band protocol. In someembodiments, the first protocol is an Industrial, Scientific and Medical(ISM) band protocol; and the second protocol is a Mobile WirelessStandards (MWS) protocol. In some embodiments, the functions furthercomprise: changing a receive mode for receiving the second wirelesssignals responsive to at least one of i) the signal power level of thefirst wireless signals not being less than the first signal powerthreshold, and ii) the signal power level of the second wireless signalsnot being greater than the second signal power threshold. In someembodiments, the functions further comprise: changing at least one of atransmit mode and a signal power level for transmitting the firstwireless signals responsive to at least one of i) the signal power levelof the first wireless signals not being less than the first signal powerthreshold, and ii) the signal power level of the second wireless signalsnot being greater than the second signal power threshold. In someembodiments, the functions further comprise: not transmitting the firstwireless signals while receiving the second wireless signals responsiveto i) a priority of the first wireless signals being less than apriority of the second wireless signals, and ii) at least one of a) thesignal power level of the first wireless signals not being less than thefirst signal power threshold; and b) the signal power level of thesecond wireless signals not being greater than the second signal powerthreshold.

The details of one or more implementations are set forth in theaccompanying drawings and the description below. Other features will beapparent from the description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 shows elements of a communication system according to oneembodiment.

FIG. 2 shows a process for the communication system of FIG. 1 accordingto an embodiment that considers the signal power levels of LTEtransmission and WiFi reception.

FIG. 3 shows a process for the communication system of FIG. 1 accordingto an embodiment that considers the signal power levels of WiFitransmission and LTE reception.

FIG. 4 shows a process for the communication system of FIG. 1 accordingto an embodiment that considers the signal power level of LTEtransmission, but not the signal power level of WiFi reception.

FIG. 5 shows a process for the communication system of FIG. 1 accordingto an embodiment that considers the signal power level of WiFitransmission, but not the signal power level of LTE reception.

FIG. 6 shows a process for the communication system of FIG. 1 accordingto an embodiment that considers the signal power level of WiFireception, but not the signal power level of LTE transmission.

FIG. 7 shows a process for the communication system of FIG. 1 accordingto an embodiment that considers the signal power level of LTE reception,but not the signal power level of WiFi transmission.

The leading digit(s) of each reference numeral used in thisspecification indicates the number of the drawing in which the referencenumeral first appears.

DETAILED DESCRIPTION

Embodiments of the present disclosure provide coexistence among multiplewireless communication technologies based on the signal power levels ofthe wireless signals. In some cases, the wireless communicationtechnologies use adjacent frequency bands, and so cause adjacent channelinterference. For example, some bands used by Mobile Wireless Standards(MWS) technologies are adjacent to the Industrial, Scientific andMedical (ISM) frequency band. In other cases, the interference resultsfrom wireless communication technologies using frequency bands thatpartially or fully overlap. For example, both WiFi and Bluetooth use theISM frequency band.

FIG. 1 shows elements of a communication system 100 according to oneembodiment. Although in the described embodiments the elements of thecommunication system 100 are presented in one arrangement, otherembodiments may feature other arrangements. For example, elements of thecommunication system 100 can be implemented in hardware, software, orcombinations thereof.

Referring to FIG. 1, the communication system 100 includes a userequipment (UE) 102 capable of communications using multiple wirelesstechnologies. The user equipment 102 can be implemented as any sort ofelectronic device capable of performing the functions described herein.For example, the user equipment 102 can be implemented as a smartphone,tablet computer, or the like. Elements of user equipment 102 can beimplemented as one or more integrated circuits.

The user equipment 102 includes multiple transceivers employingdifferent wireless technologies. In the example of FIG. 1, thetransceivers include a Mobile Wireless Standards (MWS) transceiver andan Industrial, Scientific and Medical (ISM) band transceiver. In otherembodiments, other numbers of transceivers and other combinations ofwireless technologies can be employed instead. For example, the MWStransceivers can include Long Term Evolution (LTE) transceivers,Worldwide Interoperability for Microwave Access (WiMAX) transceivers,and the like, and the ISM band transceivers can include WiFitransceivers, Bluetooth transceivers, ZigBee transceivers, and the like.The transceivers can include two MWS transceivers or two ISMtransceivers. The ISM band equipment can also include receive-onlydevices such as global positioning system (GPS) receivers, frequencymodulation (FM) radio receivers, and the like.

In the example of FIG. 1, the transceivers include a WiFi media accesscontroller (MAC) 104 and an LTE device 108. Each transceivercommunicates using one or more respective antennas. In particular, theWiFi MAC 104 uses one or more antennas 110, and the LTE device 108 usesone or more antennas 114. In some embodiments, one or more of theantennas 110, 114 can be combined.

The WiFi MAC 104 includes a receiver (WiFi Rx) 116 and a transmitter(WiFi Tx) 118. The LTE device 108 includes a receiver (LTE Rx) 120 and atransmitter (LTE Tx) 122. The WiFi MAC 104 uses antenna 110 to transmitand receive wireless WiFi protocol signals 124 (also referred to hereinas WiFi signals 124). The LTE device 108 uses antenna 114 to transmitand receive wireless LTE protocol signals 126 (also referred to hereinas LTE signals 126).

The user equipment 102 also includes an arbiter 128. The arbiter 128 canbe implemented as a processor. Processors according to variousembodiments can be fabricated as one or more integrated circuits. Thearbiter 128 receives information signals 130, 132 from the transceivers104, 108, and provides control signals 134, 136 to the transceivers 104,108. The arbiter 128 receives the information signals 130 from the WiFiMAC 104, and provides the control signals 134 to the WiFi MAC 104. Thearbiter 128 receives the information signals 132 from the LTE device108, and provides the control signals 136 to the LTE device 108.

The information signals 130, 132 include indications of the signal powerlevels of the wireless signals 124, 126. In some embodiments, theinformation signals 130, 132 include indications of other factors suchas the priorities of the traffic carried by the wireless signals 124,126, and the like. The indications of the signal power levels of thewireless signals 124, 126 can include the signal power levels of thewireless signals 124, 126 received by the receivers 116, 120, the signalpower levels of the wireless signals 124, 126 employed by thetransmitters 118, 122 to transmit the wireless signals 124, 126, and thelike. The signal power levels can include present signal power levels,as well as planned future signal power levels. The signal power level ofa wireless signal 124, 126 to be received by a receiver 116, 120 can beestimated based on system parameters, a history of received signal powerlevels, and the like. The history of received signal power levels caninclude an average of previous signal power levels, the latestinstantaneous received signal power level, and the like. The signalpower level of a wireless signal 124, 126 to be transmitted by atransmitter 118, 122 can be known in advance when controlled by anetwork, selected in advance by the transmitter 118, 122, and the like.

The arbiter 128 employs the control signals 134, 136 to control theoperation of the transceivers 104, 108. Arbiter 128 can employ thecontrol signals 134, 136 to control the signal power levels employed bythe transmitters 118, 122, the timing of the transmission of thetransmitters 118, 122, the transmission modes employed by thetransmitters 118, 122, the reception modes employed by the receivers116, 120, and the like.

FIG. 2 shows a process 200 for the communication system 100 of FIG. 1according to an embodiment that considers the signal power levels of LTEtransmission and WiFi reception. Although in the described embodimentsthe elements of the process 200 are presented in one arrangement, otherembodiments may feature other arrangements. For example, in variousembodiments, some or all of the elements of the process 200 can beexecuted in a different order, concurrently, and the like. Also someelements of the process 200 may not be performed, and may not beexecuted immediately after each other.

Referring to FIG. 2, at 202, the arbiter 128 determines whether thesignal power level of the LTE signals 126 transmitted by the LTEtransmitter 122 is less than a predetermined LTE Tx signal powerthreshold. If yes at 202, then at 204, the arbiter 128 determineswhether the signal power level of the WiFi signals 124 received by theWiFi receiver 116 is greater than a predetermined WiFi Rx signal powerthreshold. If yes at 204, then at 206, the arbiter 128 allows the LTEtransmitter 122 to transmit the LTE signals 126 while the WiFi receiver116 receives the WiFi signals 124.

If no at 202 or 204, then at 208, the arbiter 128 performs arbitration.In some cases, the arbitration involves stopping the transmission of theLTE signals 126 by the LTE transmitter 122. In other embodiments, thearbitration involves other techniques.

In some embodiments, arbitration involves a comparison of the prioritiesof the LTE signals 126 transmitted by the LTE transmitter 122 and theWiFi signals 124 received by the WiFi receiver 116. For example, if thepriority of the traffic carried by the WiFi signals 124 is greater thanthe priority of the traffic carried by the LTE signals 126, then thearbiter 128 stops the transmission of the LTE signals 126 by the LTEtransmitter 122. Conversely, if the priority of the traffic carried bythe WiFi signals 124 is less than the priority of the traffic carried bythe LTE signals 126, then the arbiter 128 stops the reception of theWiFi signals 124 by the WiFi receiver 116.

In some embodiments, instead of stopping the transmission of the LTEsignals 126 by the LTE transmitter 122 or stopping the reception of theWiFi signals 124 by the WiFi receiver 116, the arbiter 128 reduces thesignal power level of the LTE signals 126 transmitted by the LTEtransmitter 122, or changes the transmit mode of the LTE transmitter122, or both. The transmit modes can include modulation and codingschemes (MCS), multiple-input and multiple-output (MIMO) ranks, and thelike. In some embodiments, the transmit mode selection is based on thesignal power level of the LTE signals 126 transmitted by the LTEtransmitter 122. For example, the arbiter can reduce the signal powerlevel and MCS of the LTE signals 126 transmitted by the LTE transmitter122 such that the resulting signal power level is less than thepredetermined LTE Tx signal power threshold.

In some embodiments, the arbiter 128 changes the receive mode of theWiFi receiver 116 instead of, or in addition to, the above actions. Forexample, if the scheduled WiFi receive MCS is 16QAM (quadratureamplitude modulation), the arbiter 128 can reduce the WiFi receive MCSto QPSK (quadrature phase-shift keying).

FIG. 3 shows a process 300 for the communication system 100 of FIG. 1according to an embodiment that considers the signal power levels ofWiFi transmission and LTE reception. Although in the describedembodiments the elements of the process 300 are presented in onearrangement, other embodiments may feature other arrangements. Forexample, in various embodiments, some or all of the elements of theprocess 300 can be executed in a different order, concurrently, and thelike. Also some elements of the process 300 may not be performed, andmay not be executed immediately after each other.

Referring to FIG. 3, at 302, the arbiter 128 determines whether thesignal power level of the WiFi signals 124 transmitted by the WiFitransmitter 118 is less than a predetermined WiFi Tx signal powerthreshold. If yes at 302, then at 304, the arbiter 128 determineswhether the signal power level of the LTE signals 126 received by theLTE receiver 120 is greater than a predetermined LTE Rx signal powerthreshold. If yes at 304, then at 306, the arbiter 128 allows the WiFitransmitter 118 to transmit the WiFi signals 124 while the LTE receiver120 receives the LTE signals 126.

If no at 302 or 304, then at 308, the arbiter 128 performs arbitration.In some cases, the arbitration involves stopping the transmission of theWiFi signals 124 by the WiFi transmitter 118. In other embodiments, thearbitration involves other techniques.

In some embodiments, arbitration involves a comparison of the prioritiesof the WiFi signals 124 transmitted by the WiFi transmitter 118 and theLTE signals 126 received by the LTE receiver 120. For example, if thepriority of the traffic carried by the LTE signals 126 is greater thanthe priority of the traffic carried by WiFi signals 124, then arbiter128 stops the transmission of the WiFi signals 124 by the WiFitransmitter 118. Conversely, if the priority of the traffic carried byLTE signals 126 is less than the priority of the traffic carried by WiFisignals 124, then the arbiter 128 stops the reception of the LTE signals126 by the LTE receiver 120.

In some embodiments, instead of stopping the transmission of the WiFisignals 124 by the WiFi transmitter 118 or stopping the reception of theLTE signals 126 by the LTE receiver 120, the arbiter 128 reduces thesignal power level of the WiFi signals 124 transmitted by the WiFitransmitter 118, or changes the transmit mode of the WiFi transmitter118, or both. The transmit modes can include MCS, MIMO ranks, and thelike. In some embodiments, the transmit mode selection is based on thesignal power level of the WiFi signals 124 transmitted by the WiFitransmitter 118. For example, the arbiter can reduce the signal powerlevel and MCS of the WiFi signals 124 transmitted by the WiFitransmitter 118 such that the resulting signal power level is less thanthe predetermined WiFi Tx signal power threshold. In some embodiments,the arbiter 128 changes the receive mode of the LTE receiver 120, eitherinstead of, or in addition to, the above actions.

FIG. 4 shows a process 400 for the communication system 100 of FIG. 1according to an embodiment that considers the signal power level of LTEtransmission, but not the signal power level of WiFi reception. Althoughin the described embodiments the elements of the process 400 arepresented in one arrangement, other embodiments may feature otherarrangements. For example, in various embodiments, some or all of theelements of the process 400 can be executed in a different order,concurrently, and the like. Also some elements of the process 400 maynot be performed, and may not be executed immediately after each other.

Referring to FIG. 4, at 402, the arbiter 128 determines whether thesignal power level of the LTE signals 126 transmitted by the LTEtransmitter 122 is less than a predetermined LTE Tx signal powerthreshold. If yes at 402, then at 404, the arbiter 128 allows the LTEtransmitter 122 to transmit the LTE signals 126 while the WiFi receiver116 receives the WiFi signals 124. If no at 402, then at 406, thearbiter 128 performs arbitration, for example as described above withreference to FIG. 2.

FIG. 5 shows a process 500 for the communication system 100 of FIG. 1according to an embodiment that considers the signal power level of WiFitransmission, but not the signal power level of LTE reception. Althoughin the described embodiments the elements of the process 500 arepresented in one arrangement, other embodiments may feature otherarrangements. For example, in various embodiments, some or all of theelements of the process 500 can be executed in a different order,concurrently, and the like. Also some elements of the process 500 maynot be performed, and may not be executed immediately after each other.

Referring to FIG. 5, at 502, the arbiter 128 determines whether thesignal power level of the WiFi signals 124 transmitted by the WiFitransmitter 118 is less than a predetermined WiFi Tx signal powerthreshold. If yes at 502, then at 504, the arbiter 128 allows the WiFitransmitter 118 to transmit the WiFi signals 124 while the LTE receiver120 receives the LTE signals 126. If no at 502, then at 506, the arbiter128 performs arbitration, for example as described above with referenceto FIG. 3.

FIG. 6 shows a process 600 for the communication system 100 of FIG. 1according to an embodiment that considers the signal power level of WiFireception, but not the signal power level of LTE transmission. Althoughin the described embodiments the elements of the process 600 arepresented in one arrangement, other embodiments may feature otherarrangements. For example, in various embodiments, some or all of theelements of the process 600 can be executed in a different order,concurrently, and the like. Also some elements of the process 600 maynot be performed, and may not be executed immediately after each other.

Referring to FIG. 6, at 602, the arbiter 128 determines whether thesignal power level of the WiFi signals 124 received by the WiFi receiver116 is greater than a predetermined WiFi Rx signal power threshold. Ifyes at 602, then at 604, the arbiter 128 allows the LTE transmitter 122to transmit the LTE signals 126 while the WiFi receiver 116 receives theWiFi signals 124. If no at 602, then at 606, the arbiter 128 performsarbitration, for example as described above with reference to FIG. 2.

FIG. 7 shows a process 700 for the communication system 100 of FIG. 1according to an embodiment that considers the signal power level of LTEreception, but not the signal power level of WiFi transmission. Althoughin the described embodiments the elements of the process 700 arepresented in one arrangement, other embodiments may feature otherarrangements. For example, in various embodiments, some or all of theelements of the process 700 can be executed in a different order,concurrently, and the like. Also some elements of the process 700 maynot be performed, and may not be executed immediately after each other.

Referring to FIG. 7, at 702, the arbiter 128 determines whether thesignal power level of the LTE signals 126 received by the LTE receiver120 is greater than a predetermined LTE Rx signal power threshold. Ifyes at 702, then at 704, the arbiter 128 allows the WiFi transmitter 118to transmit the WiFi signals 124 while the LTE receiver 120 receives theLTE signals 126. If no at 702, then at 706, the arbiter 128 performsarbitration, for example as described above with reference to FIG. 3.

In various embodiments, various measures of received signal power levelscan be employed. If noise and interference are not addressed, then RSRP(reference signal received power for LTE) or RSSI (received signalstrength indicator) can be employed. If noise and interference are alsoaddressed, then SNR (signal-to-noise ratio), SIR (signal-to-interferenceratio), SINR (signal-to-interference-and-noise ratio), or RSRQ(reference signal received quality for LTE) can be employed. Where userequipment 102 includes a MWS transceiver and multiple ISM transceiversare employed, the ISM transmit and receive signal power levels are thoseof either ISM transceiver, or both at the same time.

The signal power thresholds discussed herein, namely the LTE Tx signalpower threshold, the LTE Rx signal power threshold, the WiFi Tx signalpower threshold, and the WiFi Rx signal power threshold, areprogrammable values, and are stored in the arbiter 128. The signal powerthresholds can be selected according to various factors such as antennaisolation and band separation between LTE and ISM, ISM and LTE receiverperformance and capability, and the like. In some embodiments, thesignal power thresholds for one transceiver can be dynamic values, forexample as a function of the signal power level of the othertransceiver.

For example, assume that the saturation point of the LTE receiver 120 is−25 dBm, the antenna isolation between the WiFi antenna 110 and the LTEantenna 114 is 12 dB, the RF filter attenuation between the WiFitransmitter 118 and the LTE receiver is 20 dB, the attenuation due toband separation between WiFi transmitter 118 and the LTE receiver 120 is10 dB, and the minimum SIR required for the LTE receiver 120 is 0 dB.Then the WiFi Tx threshold can be set at −25+12+20+10=17 dBm, and theLTE Rx threshold can be set at the WiFi transmit signal power level−12−20−10+0=the WiFi transmit signal power level −42 dBm. Therefore, ifthe WiFi transmit signal power level<17 dBm, and if the LTE receivesignal power level>WiFi Tx power level−42 dBm, the arbiter 128 allowsWiFi transmission and LTE reception at the same time.

Various embodiments feature one or more of the following advantages.From the viewpoint of an MWS base station, the downlink resource issaved from engaging in unsuccessful transactions resulting frompotentially high interference with ISM transmissions from the userequipment 102. Thus the downlink resource can be used for other userequipment 102 resulting in better resource utilization efficiency forthe base station. From the viewpoint of ISM devices in user equipment102, the ISM receive resource is saved from unsuccessful receivetransactions resulting from potentially high interference with MWSuplink packets. Note these advantages are achieved without changingexisting 3GPP LTE standards.

Various embodiments of the present disclosure can be implemented indigital electronic circuitry, or in computer hardware, firmware,software, or in combinations thereof. Embodiments of the presentdisclosure can be implemented in a computer program product tangiblyembodied in a computer-readable storage device for execution by aprogrammable processor. The described processes can be performed by aprogrammable processor executing a program of instructions to performfunctions by operating on input data and generating output. Embodimentsof the present disclosure can be implemented in one or more computerprograms that are executable on a programmable system including at leastone programmable processor coupled to receive data and instructionsfrom, and to transmit data and instructions to, a data storage system,at least one input device, and at least one output device. Each computerprogram can be implemented in a high-level procedural or object-orientedprogramming language, or in assembly or machine language if desired; andin any case, the language can be a compiled or interpreted language.Suitable processors include, by way of example, both general and specialpurpose microprocessors. Generally, processors receive instructions anddata from a read-only memory and/or a random access memory. Generally, acomputer includes one or more mass storage devices for storing datafiles. Such devices include magnetic disks, such as internal hard disksand removable disks, magneto-optical disks; optical disks, andsolid-state disks. Storage devices suitable for tangibly embodyingcomputer program instructions and data include all forms of non-volatilememory, including by way of example semiconductor memory devices, suchas EPROM, EEPROM, and flash memory devices; magnetic disks such asinternal hard disks and removable disks; magneto-optical disks; andCD-ROM disks. Any of the foregoing can be supplemented by, orincorporated in, ASICs (application-specific integrated circuits).

A number of implementations have been described. Nevertheless, variousmodifications may be made without departing from the scope of thedisclosure. Accordingly, other implementations are within the scope ofthe following claims.

What is claimed is:
 1. An apparatus comprising: a transmitter configuredto transmit, according to a first protocol, a first wireless signal,wherein a fundamental frequency of the first wireless signal is in afirst frequency band; and a receiver configured to receive, according toa second protocol, a second wireless signal, wherein a fundamentalfrequency of the second wireless signal is in a second frequency band,wherein the second frequency band is adjacent to or overlaps the firstfrequency band; and an arbiter configured to operate in a combined modeto allow the transmitter to transmit the first wireless signal accordingto the first protocol while the receiver receives the second wirelesssignal according to the second protocol, wherein the arbiter isconfigured to operate in the combined mode if i) a signal power level ofthe first wireless signal is less than a first signal power threshold,or ii) a signal power level of the second wireless signal is greaterthan a second signal power threshold.
 2. The apparatus of claim 1,wherein the arbiter is configured to operate in the combined mode if i)the signal power level of the first wireless signal is less than thefirst signal power threshold, and ii) the signal power level of thesecond wireless signal is greater than the second signal powerthreshold.
 3. The apparatus of claim 1, wherein the arbiter isconfigured to change a receive mode of the receiver responsive to thesignal power level of the first wireless signal not being less than thefirst signal power threshold.
 4. The apparatus of claim 1, wherein thearbiter is configured to change a receive mode of the receiverresponsive to the signal power level of the second wireless signal notbeing greater than the second signal power threshold.
 5. The apparatusof claim 1, wherein the arbiter is configured to reduce the signal powerlevel of the first wireless signal responsive to the signal power levelof the first wireless signal not being less than the signal powerthreshold.
 6. The apparatus of claim 1, wherein the arbiter isconfigured to change a transmit mode of the transmitter responsive tothe signal power level of the first wireless signal not being less thanthe signal power threshold.
 7. The apparatus of claim 6, wherein thearbiter is configured to change the transmit mode between i) amodulation and coding scheme mode and ii) amultiple-input-multiple-output mode.
 8. The apparatus of claim 1,wherein the arbiter is configured to, if the signal power level of thesecond wireless signal is not greater than the second signal powerthreshold, change a receive mode of the receiver between i) a quadratureamplitude modulation mode and ii) a quadrature phase-shift keying mode.9. The apparatus of claim 1, wherein the second threshold is less thanthe first threshold.
 10. The apparatus of claim 1, wherein a magnitudeof the second threshold is greater than a magnitude of the firstthreshold.
 11. A method comprising: transmitting a first wireless signalfrom a network device via a transmitter according to a first protocol,wherein a fundamental frequency of the first wireless signal is in afirst frequency band; and receiving a second wireless signal at thenetwork device via a receiver according to a second protocol, wherein afundamental frequency of the second wireless signal is in a secondfrequency band, wherein the second frequency band is adjacent to oroverlaps the first frequency band; and permitting operation in acombined mode to allow the transmitter to transmit the first wirelesssignal according to the first protocol while the receiver receives thesecond wireless signal according to the second protocol, wherein theoperation in the combined mode is permitted if i) a signal power levelof the first wireless signal is less than a first signal powerthreshold, or ii) a signal power level of the second wireless signal isgreater than a second signal power threshold.
 12. The method of claim11, comprising operating in the combined mode if i) the signal powerlevel of the first wireless signal is less than the first signal powerthreshold, and ii) the signal power level of the second wireless signalis greater than the second signal power threshold.
 13. The method ofclaim 11, further comprising changing a receive mode of the receiverresponsive to the signal power level of the first wireless signal notbeing less than the first signal power threshold.
 14. The method ofclaim 11, further comprising changing a receive mode of the receiverresponsive to the signal power level of the second wireless signal notbeing greater than the second signal power threshold.
 15. The method ofclaim 11, further comprising reducing the signal power level of thefirst wireless signal responsive to the signal power level of the firstwireless signal not being less than the signal power threshold.
 16. Themethod of claim 11, further comprising changing a transmit mode of thetransmitter responsive to the signal power level of the first wirelesssignal not being less than the signal power threshold.
 17. The method ofclaim 16, further comprising changing the transmit mode between i) amodulation and coding scheme mode and ii) amultiple-input-multiple-output mode.
 18. The method of claim 11, furthercomprising, if the signal power level of the second wireless signal isnot greater than the second signal power threshold, changing a receivemode of the receiver between i) a quadrature amplitude modulation modeand ii) a quadrature phase-shift keying mode.
 19. The method of claim11, wherein the second threshold is less than the first threshold. 20.The method of claim 11, wherein a magnitude of the second threshold isgreater than a magnitude of the first threshold.